JP2012196397A - Drum-type washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drum-type washing machine including a motor driving device capable of correcting the timing of pulse generation for boost control of a DC voltage supplied to an inverter circuit.SOLUTION: A DC voltage Vd output from a rectifier circuit 36 via smoothing capacitors 37 and 38 is applied to a first inverter circuit 25 for drive control of a drum motor 7. A control section 30 for driving the first inverter circuit generates a short-circuit signal making a short-circuit control element conductive at least during part of the period of a dewatering step with a zero-cross detection point of an AC power supply voltage as a starting point. The zero-cross serving as the starting point is corrected by comparison between Thigh and Tlow. A pulse width Tw of the short-circuit signal is set on the basis of a target voltage Vt of the DC voltage Vd, which is set according to a target rotation number Nt of the drum motor, and a detection value of the DC voltage Vd.

Description

  The present invention relates to a drum type washing machine in which a drum motor is driven by an inverter circuit in order to drive a rotating drum containing laundry at a rotational speed corresponding to each process such as washing and dehydration.

  An example of the structure of a drum-type washing / drying machine using a dehumidifying and drying system using a heat pump is shown in FIGS. FIG. 5 is a cross-sectional view showing the configuration of the main part of the drum type washing machine, and FIG. 6 is a rear view thereof.

  In this washing machine, a water tub 2 is supported in a suspended state in a washing machine body 1 by a suspension structure (not shown). A rotating drum 3 formed in a bottomed cylindrical shape is supported in the water tank 2 with its axial direction inclined downward from the front side to the back side. On the front side of the aquarium 2 is formed a clothing doorway 4 leading to the opening end of the rotary drum 3, and by opening the door 5 that closes the opening provided in the upward inclined surface on the front side of the washing machine body 1 so that it can be opened and closed. The laundry can be taken in and out of the rotary drum 3 through the clothing entrance 4.

  The rotating drum 3 is formed with a large number of through holes 6 communicating with the inside of the water tank 2 on its peripheral surface, and provided with stirring protrusions (not shown) at a plurality of positions on the inner peripheral surface. The rotating drum 3 is rotationally driven in the forward and reverse directions by a drum motor 7 attached to the back side of the water tank 2. In addition, a water injection pipe 8 and a drain pipe 9 are connected to the water tank 2 to perform water injection and drainage into the water tank 2 by controlling a water injection valve and a water discharge valve (not shown).

  When the door 5 is opened, laundry and detergent are put into the rotating drum 3 and the operation is started by an operation on the operation panel 10 provided at the upper part of the front surface of the washing / drying main body 1, for example, a water injection pipe is placed in the water tank 2. A predetermined amount of water is injected from the path 8 and the drum 3 is driven to rotate the rotating drum 3 to start the washing process. By the rotation of the rotating drum 3, the laundry accommodated in the rotating drum 3 is lifted in the rotating direction by the stirring protrusion provided on the inner peripheral wall of the rotating drum 3, and the stirring operation of dropping from the lifted appropriate height position Is repeated, so that the laundry has the effect of tapping and washing.

  After the required washing time, the dirty washing liquid is discharged from the drain pipe 9 and the washing liquid contained in the laundry is dehydrated by a dehydrating operation of rotating the rotary drum 3 at a high speed. Rinsing is performed by pouring water from the path 8. Also in this rinsing process, the laundry stored in the rotating drum 3 is rinsed by repeating the stirring operation of being lifted and dropped by the stirring protrusions by the rotation of the rotating drum 3.

  This drum type washing and drying machine is provided with a function of drying the laundry stored in the rotary drum 3, and the air in the water tank 2 is exhausted and dehumidified by the circulation air passage 11, and dried by heating. Air is blown into the water tank 2 again. In the middle of the circulation air passage 11, a dehumidifying means such as an evaporator 12, a heat pump composed of a heating means such as a condenser 13, and a circulation fan 14 serving as an air blowing means are provided. As shown in FIG. 6, the evaporator 12 and the condenser 13 are arranged at the lowest position of the circulation air passage 11 as a heat exchange part 15 with the circulation air.

  By rotating the circulation fan 14, an air flow is generated in the circulation air passage 11, and the air in the rotating drum 3 containing the laundry is circulated from the water tank 2 to the circulation fan 14 through the through holes 6. High-temperature air that is always dried by being exhausted to the introduction pipe 16 and dehumidifying the evaporator 12 located upstream of the circulation fan 14 by dew condensation and heating by heat exchange with the condenser 13. Is done.

  The dried high-temperature air is sent from the circulation fan 14 to the air duct 17 to the water tank 2 and blown into the water tank 2. The high-temperature dry air blown into the water tank 2 enters the rotating drum 3 through the through holes 6 and escapes to the water tank 2 while being exposed to laundry such as clothes, and is again introduced into the circulating air introduction pipe line 16. A drying process is implemented by the repetition of the circulation of the air in the above circulation ventilation path 11.

  In the drying process using the circulation air passage 11, foreign matter such as lint generated from laundry such as clothes is circulated in the air circulated through the circulation air passage 11, and the eyes of the evaporator and the condenser are circulated. Since clogging, clogging into the rotating part of the circulation fan 14, and a drying process such as accumulation on the inner surface of the circulation fan 14 are likely to be hindered, foreign substances in the circulation air may be trapped in the circulation air passage 11. A filter 18 for removal is provided.

  The motor driving device of the drum type washing and drying machine having the above-described configuration includes a DC voltage supply source for the inverter circuit for the drum motor 7 that rotationally drives the rotary drum 3 and the inverter circuit that drives the compressor motor for the heat pump. Is shared. Therefore, in the operation state of the compressor motor, or in the dehydration drying operation process in which the dehydration operation and the heat pump drying operation are performed simultaneously, the AC power supply current may increase and the outlet capacity may be exceeded.

  For this reason, for example, Patent Document 1 discloses that AC input or output power of the drum motor and the compressor motor at the time of the dehydration drying operation, which is the maximum power consumption of the washing / drying machine, is estimated and calculated from each motor current. It is disclosed that the power supply current is controlled so as not to exceed the outlet capacity upper limit value. Thereby, the DC voltage of the inverter circuit can be supplied stably.

  Patent Document 2 discloses means for short-circuiting the AC power supply via a reactor connected in series with the AC power supply between the rectifier circuit for supplying the DC voltage Vd to the inverter circuit for driving the motor and the AC power supply. A provided motor drive circuit is disclosed. The short-circuit means performs a short-circuit operation during a period set by the pulse width Tw of the control signal, starting from a predetermined delay time Td from the zero crossing time of the AC power supply. The power factor is supplied to the inverter circuit while keeping the power factor of the power supply device at the maximum value even if the power supply voltage fluctuates by improving the power factor by short-circuiting the power supply once or multiple times in the half cycle of the power supply voltage Vs. The DC voltage Vd can be controlled to be constant.

JP 2008-54811 A JP 2004-72806 A

In order to improve the function of the washing and drying machine, for example, it is desired to increase the rotation speed of the drum motor in the dehydration process, for example, to increase the maximum rotation speed from the conventional 1200 min ⁻¹ to 1600 min ⁻¹ . Yes. However, considering the increase in cost and energy saving, it is desirable to enable high-speed rotation without increasing the size of the motor.

  However, in order to increase the rotation speed without increasing the size of the motor, it is necessary to increase the power supplied to the motor. On the other hand, when the supplied power is increased, the DC voltage supplied to the inverter circuit is reduced. In particular, in the dehydration process during the operation including the dehydration process and the drying process, the decrease in the DC power supply voltage becomes very large during the parallel drive period in which the drum motor and the compressor motor are simultaneously driven.

  Further, in the drying process, it is desired to maintain the DC voltage in order to stably operate the circulation fan even under a situation where the DC voltage decreases with a decrease in the power supply voltage or an increase in the compressor motor output for the heat pump.

  In order to avoid such a drop in the DC voltage and maintain a sufficient level of DC voltage and supply sufficient power to the drum motor and the like, we studied boosting the DC voltage with a booster circuit.

  The short-circuit means necessary for the operation of the booster circuit is controlled at the zero cross timing. The zero cross is constituted by a photocoupler or the like, and the zero cross is detected by the edge of the pulse signal to be detected according to the voltage of the AC power supply. However, since the deviation Ta and Tb between the detection of the edge at the rising and falling edges of the pulse signal of the photocoupler and the zero cross point of the AC power supply are shifted by about several hundred μs, the peak value of the power supply current and The current value applied to each smoothing capacitor changes. Therefore, it is necessary to correct the deviations Ta and Tb between the detection of the edge at the rise and fall of the pulse signal and the zero cross point of the AC power supply. The techniques disclosed in Patent Documents 1 and 2 do not meet such requirements.

  Therefore, according to the present invention, the DC voltage supplied to the inverter circuit is boosted by the booster circuit, and the deviation of the rise and fall of the pulse signal of the zero-cross detection circuit that is a reference for operating the short-circuit means necessary for the operation of the booster circuit is corrected. Then, it aims at providing the drum type washing machine provided with the motor drive device which enables the stable circuit operation | movement.

  In order to solve the above problems, a drum-type washing machine of the present invention includes a rotating drum having a rotation center axis in a horizontal direction or an inclined direction, a water tank holding the rotating drum rotatably, and the rotating drum. A drum motor that is driven to rotate, a rectifier circuit that rectifies alternating current from an AC power supply, a smoothing capacitor connected to the output terminal of the rectifier circuit, and connected in parallel to the smoothing capacitor to drive and control the drum motor A first inverter circuit, a reactor connected in series with one end of the AC power supply and one end of the rectifier circuit, and one end connected between one end of the reactor and one end of the rectifier circuit input side, the other end Comprises a short circuit having a short circuit control element connected to the other end of the AC power supply, and a controller for driving the first inverter circuit and controlling a series of washing operations. The control unit includes a zero-cross detection circuit that detects a zero-cross of the voltage of the AC power source, a rotation speed detection unit that detects the rotation speed of the drum motor, and a DC voltage Vd that is output across the smoothing capacitor. A DC voltage detection unit for detecting; and a short-circuit signal generation unit for generating a short-circuit signal for conducting the short-circuit control element, wherein the short-circuit signal generation unit transmits the short-circuit signal to the AC in at least a partial period of a dehydration process. A zero-cross detection point of the power supply voltage is generated as a starting point, and the pulse width Tw of the short circuit signal is set to the target voltage Vt of the DC voltage Vd set according to the target rotational speed Nt of the drum motor and the DC voltage Vd. Based on the detection value, the short-circuit voltage is set so that the DC voltage Vd has a certain magnitude necessary for obtaining the target rotational speed Nt of the drum motor. A drum-type washing machine that controls a pulse width Tw of a signal, and detects a rising edge and a falling edge of a pulse signal at a zero cross point by an edge of the pulse signal detected from the zero cross detection circuit. And the zero-cross point of the AC power supply are corrected to the same time deviations Ta and Tb.

  According to the drum type washing machine of the present invention, the short circuit signal is generated from the zero crossing detection point of the AC power supply without the time difference between the rising time and the falling time of the zero crossing detection circuit. The peak value, the voltage applied to each smoothing capacitor, and the current value are the same. A smoothing capacitor with high withstand voltage and long life is required by improving the power factor and averaging the smoothing capacitor voltage and current. Can be realized at low cost, and by averaging the current value, the load on the parts can be reduced, so that the DC voltage Vd can be set higher, and the dehydration drying operation in which the dehydration operation and the heat pump drying operation are performed simultaneously. In the process, a drum-type washing machine that realizes faster dehydration rotation speed than before, or can maintain the high rotation state of the heat pump, reducing the washing and drying time. It can be provided.

The block diagram which shows the motor drive device of the drum type washing-drying machine in Embodiment 1 of this invention The figure which shows the operation at the time of the short circuit with the short circuit of the motor drive device (A) The figure which shows the change of the input current to the full-wave rectifier circuit by the operation | movement of the short circuit of the motor drive device. (B) The input current to the full-wave rectifier circuit in the conventional motor drive device without the short circuit. Figure The figure for demonstrating the setting example of the step-up operation of DC voltage of the motor drive device Sectional drawing which shows the structure of the drum type washing-drying machine using the dehumidification drying system by the heat pump of a prior art example Inside rear view of the drum type washing and drying machine Detailed diagram of zero cross detection circuit Diagram showing the deviation between the zero cross of the zero cross detection circuit and the zero cross point of the AC power supply The figure which shows the current peak value input to the smoothing capacitor when the zero cross is shifted The figure which shows the AC power source current peak value every half cycle when the zero cross shifts

  The drum type washing machine of the present invention can take the following aspects based on the above-described configuration.

  That is, in the above-described configuration, at least a compressor is provided, and a drying unit that introduces air in the water tank through a circulation path to dehumidify and heat, a compressor motor that drives the compressor, and the smoothing capacitor are connected in parallel. And a second inverter circuit that drives and controls the compressor motor, and the control unit is configured to drive the second inverter circuit together with the first inverter circuit, and the control unit includes: When the drum motor and the compressor motor are simultaneously driven in parallel to perform an operation including a dehydration process and a drying process, the zero cross point deviations Ta and Tb detected by the zero cross detection circuit are set to the same time deviation. Control the pulse width Tw of the short circuit signal generated by the control unit to be corrected, and control to boost the DC voltage Vd Preferred.

  In the dehydration step, the boost control of the DC voltage Vd by the short circuit is not performed during the period in which the target rotational speed Nt is equal to or less than a predetermined magnitude, and in the period after the target rotational speed Nt exceeds the predetermined magnitude. The boost control of the DC voltage Vd can be performed.

  In the washing process, the short circuit signal can be set to a constant pulse width Tw corresponding to the DC voltage Vd lower than the target voltage Vt in the dehydration process.

  In the drying process, when the compressor motor is driven to rotate, the short circuit can be operated to increase the DC voltage Vd.

  In the above configuration, the control unit uses a photocoupler or the like when the pulse signal rises and falls at the zero cross point due to the edge of the pulse signal detected from the zero cross detection circuit that detects the zero cross of the AC power supply voltage. It is possible to perform control for correcting the deviations Ta and Tb between the detection of the edge and the zero cross point of the AC power supply to the same time deviation.

  In the above-described configuration, the control unit that corrects the deviations Ta and Tb of the zero-cross point detected by the zero-cross detection circuit to the same time deviation includes the high signal time High and the low signal time Tlow of the pulse of the zero-cross detection circuit. By comparison, it is possible to correct the half-cycle T / 2 after the half-cycle pulse as the next zero-cross point from the zero-cross point of the edge when the pulse having the longer time is generated.

  Alternatively, in the above configuration, the control unit that corrects the deviations Ta and Tb of the zero-cross point detected by the zero-cross detection circuit to the same time deviation may include the high signal time Thigh and the low signal time Tlow of the pulse of the zero-cross detection circuit. And the generation of the short-circuit signal pulse can be corrected so as to be delayed by a time of | High-Tlow | / 2 from the zero cross point of the edge when the pulse of the longer pulse is generated.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram showing a motor driving device of a drum type washing / drying machine according to an embodiment of the present invention. The overall structure of the drum-type washing and drying machine in the present embodiment is the same as that shown in FIGS.

  1 has a function of controlling driving of a drum motor 7, a fan motor for driving a circulation fan 14 (see FIG. 5), and a compressor motor for a heat exchange unit 15 (see FIG. 6). In the figure, only the part related to the driving of the drum motor 7 and the compressor motor 20 is shown. Each of the drum motor 7 and the compressor motor 20 is a permanent magnet synchronous motor including a stator having a three-phase winding and a rotor having a two-pole permanent magnet.

  The drum motor 7 is provided with three rotor position detection elements 21a, 21b, and 21c for detecting the rotor position. The rotor position detection elements 21a to 21c output a rotor position signal for every electrical angle of 60 degrees corresponding to the rotor magnetic pole position. The drum motor 7 is rotationally driven by the first inverter circuit 22. The first inverter circuit 22 is configured by connecting six switching elements 23 in a three-phase bridge, and a flywheel diode 24 is connected to each switching element 23 in parallel. The on / off state of each switching element 23 is PWM controlled by the first drive circuit 25.

  On the other hand, the compressor motor 20 is rotationally driven by the second inverter circuit 26. The compressor motor 20 has no rotor position detection element, and is position sensorless sine wave drive controlled based on a signal from the current detection means, for example. Similarly to the first inverter circuit 22, the second inverter circuit 26 is configured by connecting six switching elements 27 in a three-phase bridge, and a flywheel diode 28 is connected to each switching element 27 in parallel. The on / off state of each switching element 27 is PWM controlled by the second drive circuit 29.

  Actually, the motor drive device is also provided with a third inverter circuit and a third drive circuit for driving the fan motor for the circulation fan 14, but the configuration and operation thereof are the same as those of the second inverter circuit. Since it is the same as that of No. 26 and a 2nd drive circuit, illustration and description are abbreviate | omitted.

  The first drive circuit 25 and the second drive circuit 29 operate under the control of the control unit 30. A rotor position signal output from the rotor position detecting elements 21 a to 21 c of the drum motor 7 is input to the control unit 30. Based on this rotor position signal, the first drive circuit 25 performs PWM control of the on / off state of each switching element 23, thereby controlling the energization of the three-phase winding of the stator of the drum motor 7 and synchronously driving the rotor. Is done. Although not shown, the control unit 30 further includes a rotation speed detection unit that detects the rotation speed of the rotor, that is, the rotation speed Nd of the drum motor 7 based on the rotor position signals from the three rotor position detection elements 21a to 21c. The rotation speed detection unit detects the cycle every time the state of the three rotor position signals changes, and calculates the rotation frequency Nd of the drum motor 7 from the cycle.

  Supply of electric power to the first and second inverter circuits 22 and 26 is performed by an AC power supply 31, a short circuit 32, and a rectifier 33. That is, a DC voltage Vd is generated from the AC voltage Vs supplied from the AC power supply 31 by the short circuit 32 and the rectifier 33 and applied to the first and second inverter circuits 22 and 26.

  The short circuit 32 includes a reactor 34 connected in series between the AC power supply 31 and the rectifying unit 33, and a short circuit control element 35 connected in parallel to the AC power supply 31 via the reactor 34. The short-circuit control element 35 can be constituted by a power semiconductor switching element such as a diode bridge and IGBT, a bipolar transistor, or a MOSFET, for example.

  The rectifier 33 includes a full-wave rectifier circuit 36, and a series circuit of smoothing capacitors 37 and 38 is connected to the full-wave rectifier circuit 36 in parallel. The DC voltage Vd across the smoothing capacitors 37 and 38 is applied to the first inverter circuit 22 and the second inverter circuit 26, and the DC power is converted into three-phase AC power and supplied to the drum motor 7 and the compressor motor 20. Is done.

  In addition, a zero cross detection circuit 39 is provided, and the AC voltage Vs across the AC power supply 31 is input. The zero-cross detection circuit 39 outputs a zero-cross detection signal that switches from the High signal to the Low signal or from the Low signal to the High signal at the timing when the polarity of the alternating voltage Vs passes through the zero-cross point and changes the polarity.

  The control unit 30 also includes a DC voltage detection unit that detects the DC voltage Vd across the smoothing capacitors 37 and 38, and thus the DC voltage Vd applied to the first and second inverter circuits 22 and 26. Furthermore, the control unit 30 includes a short circuit signal generation unit, and generates a short circuit signal Ps for conducting the short circuit control element 35 of the short circuit 32 at least during a partial period of the dehydration process.

  The motor drive device having the above configuration is characterized by the operation of the short circuit 32. The short circuit 32 shorts the AC voltage Vs through the reactor 34 when the short control element 35 is turned on. In the short circuit state, the power of the AC voltage Vs is accumulated in the reactor 34, and the accumulated power is supplied to the rectifier 33 when the short circuit control element 35 is turned off. The supplied power is converted into direct current by the full-wave rectifier circuit 36, and the smoothing capacitors 37 and 38 are charged to increase the output direct current voltage Vd.

  In order to effectively perform such boosting operation, the short circuit signal generation unit of the control unit 30 generates the short circuit signal Ps every half cycle of the power supply voltage Vs starting from the zero cross detection point detected by the zero cross detection circuit 39. Generate. Further, the target voltage Vt with respect to the DC voltage Vd is set according to the target rotational speed Nt of the drum motor 7, and the pulse width Tw of the short circuit signal Ps is set based on the target voltage Vt and the detected value of the DC voltage Vd. The For example, the pulse width Tw is controlled so that the direct-current voltage Vd becomes a constant magnitude necessary for obtaining the target rotational speed Nt of the drum motor 7.

  An example of the operation of the short circuit 32 is shown in FIG. A short circuit signal Ps having a pulse width Tw is generated every half cycle starting from the zero crossing detection point of the voltage Vs of the AC power supply 31. During the High period of the short circuit signal Ps, the short circuit control element 35 is turned on, a short circuit current due to the AC voltage Vs flows, and electric power is accumulated in the reactor 34. When the short circuit signal Ps becomes Low, the auxiliary input current Ia based on the electric power accumulated in the reactor 34 is passed through the full-wave rectifier circuit 36. The auxiliary input current Ia is superimposed on the current due to the AC voltage Vs to form an input current to the full-wave rectifier circuit 36. By superimposing the auxiliary input current Ia, the DC voltage Vd across the smoothing capacitors 37 and 38 can be increased.

  FIG. 3A shows how the input current Ib to the full-wave rectifier circuit 36 increases due to the auxiliary input current Ia. For comparison, FIG. 3B shows an input current Ib to the full-wave rectifier circuit 36 when the short circuit 32 is not operated.

In the dehydration process, as shown in FIG. 4, pressure increase control is performed in accordance with the target rotational speed Nt at each stage. FIG. 4 shows the target rotational speed Nt at each stage of the dehydration process. The abscissa indicates each stage of the process, and processing is performed in the order of preliminary dewatering, cloth peeling, and main dewatering. In the preliminary dehydration, Nt = 320 min ⁻¹ , and when the cloth is peeled off, the rotation speed is lower, so that the pressure increase control is unnecessary. In addition, the driving of the compressor is started for the heat pump operation from the stage of cloth peeling.

In this dehydration stage, control for gradually increasing the rotational speed is performed. At this stage, since the drum motor and the compressor motor are operated in parallel, the DC voltage Vd may decrease. Therefore, it is desirable to perform a boosting operation when entering the final dehydration stage. Therefore, the target voltage Vt to be boosted is changed according to the target rotation speed Nt of the drum motor 7. For example, the boost control is not performed during a period in which the target rotation speed Nt is 420 min ⁻¹ . During the period in which the target rotational speed Nt is 420 to 1600 min ⁻¹ , the target voltage Vt is set to 300 V, and the pulse width Tw of the short circuit signal Ps is controlled. The reason why the boost control is not performed during the period up to 420 min ⁻¹ is that the beat sound generated by the reactor is conspicuous in the low rotation speed state, and the necessity for boosting is low.

  In the drying process, control is performed to increase the rotation speed of the circulation fan by increasing the pressure. The target voltage Vt at this time is about 250V, for example. As a result, even if the power supply is lowered or the compressor motor input is increased and the DC voltage is lowered, the circulating fan can be stably operated.

  However, the short circuit signal generation unit of the control unit 30 generates the short circuit signal Ps every half cycle of the power supply voltage Vs starting from the zero cross detection point detected by the zero cross detection circuit 39, but the pulse detected from the zero cross detection circuit 39 At the zero cross point due to the edge of the signal, the difference between the detection of the edge at the rise and fall of the pulse signal and the zero cross point of the AC power supply is shifted from the time of rise Ta to the fall Tb.

  FIG. 7 shows a detailed view of the zero cross detection circuit 39, and FIG. 8 shows a shift between the zero cross of the zero cross detection circuit and the zero cross point of the AC power supply.

  Current peaks input to the smoothing capacitors 37 and 38 are shifted because the time Ta and Tb are shifted from the detection of the edge of the pulse signal of the zero cross detection circuit 39 at the time of rising and falling and the zero cross point of the AC power supply. The values are different as shown in FIG. Similarly, as shown in FIG. 10, the AC power supply current has a peak value shifted every half cycle. Therefore, in order to correct the deviations Ta and Tb of the zero cross point detected by the zero cross detection circuit 39, the high signal time High of the pulse of the zero cross detection circuit 39 and the low signal time Tlow are compared, and the time is long. From the zero cross point of the edge when the other pulse is generated, the half cycle T / 2 after the pulse is corrected as the next zero cross point. For example, referring to FIG. 8, since the High time is about 10.3 ms and the Tlow time is about 9.7 ms, and the High time is longer, the zero crossing at the time of generation of the High pulse occurs. A point (a point shifted by Ta from the rising zero cross of the AC power supply) is defined as a zero cross, and the next zero cross is defined as a next zero cross T / 2 after the zero cross point at the time of generation of the High pulse. By doing in this way, since the value of Ta and Tb can be made the same, the current peak value input to the smoothing capacitors 37 and 38 becomes the same value, and the AC power supply current peak value every half cycle of the AC power supply current. Can be corrected to the same value.

The correction of the deviation is made by comparing the high signal time Thigh of the pulse of the zero cross detection circuit with the low signal time Tlow, and the time of | High−Tlow | / 2 from the zero cross point of the edge when the longer pulse is generated. It is also possible to correct so as to delay the generation of the short-circuit signal pulse by the amount. For example, referring to FIG. 8, since the High time is about 10.3 ms and the Tlow time is about 9.7 ms, and the High time is longer, the zero crossing at the time of generation of the High pulse occurs. By delaying the point (the point shifted by Ta from the zero crossing of the AC power supply rise) by | High-Tlow | /2=0.3 ms and generating pulses, the values of Ta and Tb can be made the same, so that smoothing The current peak values input to the capacitors 37 and 38 have the same value, and the AC power supply current peak value for each half cycle of the AC power supply current can be corrected to the same value.

  As described above, the drum type washing and drying machine of the present embodiment includes the short circuit 32 including the reactor 34 and the short circuit control element 35, and the short circuit signal for conducting the short circuit control element 35 is transmitted to the zero cross of the voltage of the AC power supply 31. A detection point is generated as a starting point. The pulse width Tw of the short circuit signal is set based on the target voltage Vt of the DC voltage Vd set according to the target rotation speed Nt of the drum motor 7 and the detected value of the DC voltage Vd. At this time, the zero crossing as a starting point is compared and corrected for High and Tlow, so that the DC voltage Vd supplied to the inverter circuits 22 and 29 can be boosted under appropriate conditions according to the situation. The current and the current peak of the smoothing capacitor can be controlled without shifting every half cycle, and the driving of the drum motor 7, the fan motor for driving the circulation fan 14, and the compressor motor 20 for the heat exchange unit can be stably controlled. It is possible.

  According to the drum type washing machine of the present invention, it is possible to stably supply a DC voltage to the inverter circuit, which is useful for a washing and drying machine using a dehumidifying and drying method using a heat pump.

DESCRIPTION OF SYMBOLS 1 Washing machine main body 2 Water tank 3 Rotating drum 4 Clothes entrance / exit 5 Door 6 Through hole 7 Drum motor 8 Water injection line 9 Drainage line 10 Operation panel 11 Circulation ventilation path 12 Evaporator 13 Condenser 14 Circulation fan 15 Heat exchange part 16 Circulation Air introduction line 17 Blower line 18 Filter 20 Compressor motors 21a, 21b, 21c Rotor position detection element 22 First inverter circuit 23, 27 Switching element 24, 28 Flywheel diode 25 First drive circuit 26 Second inverter circuit 29 Second drive circuit 30 Control unit 31 AC power source 32 Short circuit 33 Rectifier unit 34 Reactor 35 Short circuit control element 36 Full wave rectifier circuit 37, 38 Smoothing capacitor 39 Zero cross detection circuit

Claims (4)

A rotating drum having a central axis of rotation in the horizontal or inclined direction;
A water tank rotatably holding the rotating drum;
A drum motor for rotating the rotary drum;
A rectifier circuit for rectifying the alternating current from the alternating current power supply;
A smoothing capacitor connected to the output terminal of the rectifier circuit;
A first inverter circuit connected in parallel to the smoothing capacitor and drivingly controlling the drum motor;
One end of the AC power supply and one end of the rectifier circuit connected in series, one end connected between one end of the reactor and one end of the rectifier circuit input side, the other end is the other end of the AC power supply A short circuit having a short circuit control element connected to,
A controller that drives the first inverter circuit and controls a series of washing operations;
The control unit is output to both ends of a zero cross detection circuit that detects a zero cross of the voltage of the AC power supply using a photocoupler, a rotation speed detection unit that detects the rotation speed of the drum motor, and the smoothing capacitor. A DC voltage detection unit that detects a DC voltage Vd, and a short circuit signal generation unit that generates a short circuit signal for conducting the short circuit control element at a zero cross timing of an AC power source that detects a short circuit signal from a zero cross detection circuit,
The short-circuit signal generation unit generates the short-circuit signal from a zero-cross detection point of the AC power supply voltage as a starting point at least during a partial period of the dehydration process, and determines the pulse width Tw of the short-circuit signal as a target rotational speed of the drum motor. It is set based on the target voltage Vt of the DC voltage Vd set according to Nt and the detected value of the DC voltage Vd, and the DC voltage Vd is necessary for obtaining the target rotational speed Nt of the drum motor. A drum type washing machine characterized by controlling the pulse width Tw of the short circuit signal so as to have a constant magnitude,
Drum that corrects deviations Ta and Tb between the detection of the edge of the pulse signal at the rise and fall of the pulse signal and the zero cross point of the AC power source at the zero cross point detected by the zero cross detection circuit to the same time deviation Type washing machine. Drying means comprising at least a compressor, introducing air in the water tank through a circulation path, dehumidifying and heating;
A compressor motor for driving the compressor;
A second inverter circuit connected in parallel to the smoothing capacitor and drivingly controlling the compressor motor;
The control unit is configured to drive the second inverter circuit together with the first inverter circuit,
The controller controls the zero cross point deviations Ta and Tb detected from the zero cross detection circuit when simultaneously driving the drum motor and the compressor motor in parallel to perform an operation including a dehydration step and a drying step. The drum-type washing machine according to claim 1, wherein control is performed so as to control the pulse width Tw of the short-circuit signal generated by the control unit that corrects the deviation of the same time to boost the DC voltage Vd.   The control unit for correcting the zero cross point deviations Ta and Tb detected by the zero cross detection circuit to the same time deviation compares the high signal time High of the pulse of the zero cross detection circuit with the low signal time Tlow. The drum type washing machine according to claim 1 or 2, wherein a half cycle T / 2 after the pulse is corrected as the next zero cross point from the zero cross point of the edge when the longer pulse is generated.   The control unit for correcting the zero cross point deviations Ta and Tb detected by the zero cross detection circuit to the same time deviation compares the high signal time High of the pulse of the zero cross detection circuit with the low signal time Tlow. 3. The drum type washing machine according to claim 1, wherein correction is performed so as to delay the generation of the pulse of the short circuit signal by a time of | High−Tlow | / 2 from the zero cross point of the edge when the longer pulse is generated.

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